Probing the Heavy Flavor Content in t tbar Events and Using t tbar Events as a Calibration Tool at CMS

We present two analyses dedicated to measure the ratio of branching ratios of the top quark, R=B(t->Wb)/(t->Wq) (where q=d,s,b), using ttbar events with either one or two prompt isolated leptons (e or mu) in the final state. Furthermore the framework of the dileptonic analysis was used also for a feasibility study of the measurement of b-tagging efficiency, by assuming the R value to be the Standard Model one. Data-driven techniques to control the background in the selected events are discussed and the expected simulation results are presented.Comment: 6 pages, To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C09072

Aspirin and the Primary Prevention of Cardiovascular Diseases. An Approach Based on Individualized, Integrated Estimation of Risk

While the use of aspirin in the secondary prevention of cardiovascular (CVD) is well established, aspirin in primary prevention is not systematically recommended because the absolute CV event reduction is similar to the absolute excess in major bleedings. Recently, emerging evidence suggests the possibility that the assumption of aspirin, may also be effective in the prevention of cancer. By adding to the CV prevention benefits the potential beneficial effect of aspirin in reducing the incidence of mortality and cancer could tip the balance between risks and benefits of aspirin therapy in the primary prevention in favour of the latter and broaden the indication for treatment with in populations at average risk. While prospective and randomized study are currently investigating the effect of aspirin in prevention of both cancer and CVD, clinical efforts at the individual level to promote the use of aspirin in global (or total) primary prevention could be already based on a balanced evaluation of the benefit/risk ratio

Recent Belle II results on BSM physics

We report on recent results obtained by the Belle II experiment related to searches for beyond-the-standard-model physics. The $B$ meson decay data sample used corresponds to an integrated luminosity of $L = 189$ fb$^{-1}$. In recent years, discrepancies from standard-model predictions, which suggest violation of lepton-flavor universality, have emerged in multiple measurements of $B$-meson decays. In this document two analyses aimed to search for violation of the light-lepton universality are reported: the inclusive $R(X_{e/\mu})$ measurement and an angular analysis of the $B^0 \to D^{*-} l^+ \nu_l$, with $l=e,\mu$, decays. In addition, beyond-the-standard-model physics can manifests itself with the production of new particles. The search for a long-lived spin-0 particle in $b\to s$ transitions, and its interpretation in two dark sector models, is reported.Comment: Presented at DIS2023: XXX International Workshop on Deep-Inelastic Scattering and Related Subjects, Michigan State University, USA, 27-31 March 2023. Updated version includes a reference to a preprint which is just release

Chronic heart failure is characterized by altered mitochondrial function and structure in circulating leucocytes

Oxidative stress is currently viewed as a key factor in the genesis and progression of Heart Failure (HF). The aim of this study was to characterize the mitochondrial changes linked to oxidative stress generation in circulating peripheral blood mononuclear cells isolated from chronic HF patients (HF_PBMCs) in order to highlight the involvement of mitochondrial dysfunction in the pathophysiology of HF. To assess the production of reactive oxygen species (ROS), mitochondrial function and ultrastructure and the mitophagic flux in circulating PBMCs we enrolled 15 patients with HF and a control group of ten healthy subjects. The HF_PBMCs showed a mitochondrial population consisting of damaged and less functional organelles responsible of higher superoxide anion production both at baseline and under in vitro stress conditions, with evidence of cellular apoptosis. Although the mitophagic flux at baseline was enhanced in HF_PBMCs at level similar to those that could be achieved in control PBMCs only under inflammatory stress conditions, the activation of mitophagy was unable to preserve a proper mitochondrial dynamics upon stress stimuli in HF. In summary, circulating HF_PBMCs show structural and functional derangements of mitochondria with overproduction of reactive oxidant species. This mitochondrial failure sustains a leucocyte dysfunctional status in the blood that may contribute to development and persistence of stress conditions within the cardiovascular system in HF

Prognostic value of heart rate reserve in patients with suspected coronary artery disease undergoing stress myocardial perfusion imaging

Background. Chronotropic incompetence is common in patients with cardiovascular disease and is associated with increased risk of adverse events. We assessed the incremental prognostic value of heart rate reserve (HRR) over stress myocardial perfusion single-photon emission computed tomography (MPS) findings in patients with suspected coronary artery disease (CAD). Methods. We studied 866 patients with suspected CAD undergoing exercise stress-MPS as part of their diagnostic program. The primary study endpoint was all-cause mortality. All patients were followed for at least 5 years. HRR was calculated as the difference between peak exercise and resting HR, divided by the difference of age-predicted maximal and resting HR and expressed as percentage. Results. During 7 years follow-up, 61 deaths occurred, with a 7% cumulative event rate. Patients experiencing death were older (P < .001), and had a higher prevalence of male gender (P < .001) and diabetes (P < .05). Patients with event also had lower values of HRR (65% ± 27% vs 73% ± 18%, P < .0001) and higher prevalence of stress-induced myocardial ischemia (25% vs 8%, P < .0001). Male gender, HRR and stress-induced ischemia were independent predictors of all-cause mortality (all P < .01). HRR improved the prognostic power of a model including clinical data and MPS findings, increasing the global v2 from 66 to 82 (P < .005). Conclusions. Chronotropic incompetence has independent and incremental prognostic value in predicting all-cause mortality in patients with suspected CAD undergoing exercise stress-MPS. Hence, the evaluation of HRR may further improve patients’ risk stratification

Characterization of fast-twitch and slow-twitch skeletal muscles of calsequestrin 2 (CASQ2)-knock out mice: unexpected adaptive changes of fast-twitch muscles only

This study investigates the functional role of calsequestrin 2 (CASQ2) in both fast-twitch and slow-twitch skeletal muscles by using CASQ2 12/ 12 mice; CASQ2 is expressed throughout life in slow-twitch muscles, but only in the developmental and neonatal stages in fast-twitch muscles. CASQ2 12/ 12 causes increase in calsequestrin 1 (CASQ1) expression, but without functional changes in both muscle types. CASQ2 12/ 12 mice have ultrastructural changes in fast-twitch muscles only, i.e., formation of pentads and stacks in the sarcoplasmic reticulum

Ablation rate after radioactive iodine therapy in patients with differentiated thyroid cancer at intermediate or high risk of recurrence: a systematic review and a meta-analysis

Purpose We performed a systematic review and a meta-analysis to investigate the successful ablation rate after radioiodine (RAI) administration in patients with differentiated thyroid cancer (DTC) at intermediate-high risk of recurrence. Methods: A comprehensive literature search of the PubMed, Scopus, and Web of Science databases was conducted according to the PRISMA statement. Results: The final analysis included 9 studies accounting for 3103 patients at intermediate-high risk of recurrence. In these patients, the successful ablation rates ranged from 51 to 94% with a 71% pooled successful ablation and were higher in intermediate (72%) than in high (52%)-risk patients. Despite the rigorous inclusion standards, a significant heterogeneity among the evaluated studies was observed. Higher administered RAI activities are associated with a lower successful ablation rate in the whole population and in the subgroup of high-risk patients. Furthermore, pooled recurrence rate in intermediate-risk patients achieving successful ablation was only 2% during the subsequent 6.4-year follow-up while the pooled recurrence rate was 14% in patients who did not achieve a successful ablation. Conclusion: In a large sample of 3103 patients at intermediate-high risk of persistent/recurrent disease, 71% of patients achieved a successful ablation. In these intermediate-risk patients, the probability of subsequent recurrence is low and most recurrence occurred in those with already abnormal findings at the first control

In vitro characterization of mitochondrial function and structure in rat and human cells with a deficiency of the NADH:ubiquinone oxidoreductase Ndufc2 subunit

Ndufc2, a subunit of the NADH:ubiquinone oxidoreductase, plays a key role in the assembly and activity of complex I within the mitochondrial OXPHOS chain. Its deficiency has been shown to be involved in diabetes, cancer and stroke. To improve our knowledge on the mechanisms underlying the increased disease risk due to Ndufc2 reduction, we performed the present in vitro study aimed at the fine characterization of the derangements in mitochondrial structure and function consequent to Ndufc2 deficiency. We found that both fibroblasts obtained from skin of heterozygous Ndufc2 knock-out rat model showed marked mitochondrial dysfunction and PBMC obtained from subjects homozygous for the TT genotype of the rs11237379/NDUFC2 variant, previously shown to associate with reduced gene expression, demonstrated increased generation of reactive oxygen species and mitochondrial damage. The latter was associated with increased oxidative stress and significant ultrastructural impairment of mitochondrial morphology with a loss of internal cristae. In both models the exposure to stress stimuli, such as high-NaCl concentration or LPS, exacerbated the mitochondrial damage and dysfunction. Resveratrol significantly counteracted the ROS generation. These findings provide additional insights on the role of an altered pattern of mitochondrial structure-function as a cause of human diseases. In particular, they contribute to underscore a potential genetic risk factor for cardiovascular diseases, including stroke